Simulative methods are nowadays frequently used in metrology for the simulation of measurement uncertainty and the prediction of errors that may occur during measurements. In coordinate metrology, such methods are primarily used with the typical three-axis Coordinate Measuring Machines (CMMs), and lately, also with mobile measuring systems. However, no similar simulative models have been developed for five-axis systems in spite of their growing popularity in recent years. This paper presents the numerical model of probe head errors for probe heads that are used in five-axis coordinate systems. The model is based on measurements of material standards (standard ring) and the use of the Monte Carlo method combined with select interpolation methods. The developed model may be used in conjunction with one of the known models of CMM kinematic errors to form a virtual model of a five-axis coordinate system. In addition, the developed methodology allows for the correction of identified probe head errors, thus improving measurement accuracy. Subsequent verification tests prove the correct functioning of the presented model.

Currently the Coordinate Measuring Technique is facing new challenges both in terms of used methodology and a speed of measurement. More and more often modern optical systems or multisensor systems replace classic solutions. Measurement performed using the optical system is more vulnerable to incorrect points acquisition due to such factors as an inadequate focus or parameters of applied illumination. This article examines the effect of an increasing illumination on the measurement result. A glass reference plate with marked circles and a hole plate standard were used for the measurements performed on a multi-sensor machine Zeiss O’ Inspect 442. The experiment consisted of measurements of standard objects with different values of the backlight at the maximum magnification. Such approach allows to assess the influence of controlled parameter on errors of diameter and form measurements as well as an uncertainty of measurements by determination of ellipses of point repeatability. The analysis of the obtained results shows that increasing backlight mainly affects the result of the diameter measurement.

Modeling of various measuring systems used in coordinate metrology is a very relevant and current topic. Functional models of measuring systems are used in simulative methods as so called ‘virtual models’ and are used mainly for determination of measurement uncertainty and prediction of errors that may occur during the measurement. Virtual models have already been developed for coordinate measuring machines and articulated arm coordinate measuring machines and are currently under development for other, state-of-the-art measuring systems. They include Laser Tracking systems, optical coordinate measuring machines (CMMs) and five-axis measuring systems. The first step towards development of virtual model for the latter system was presented in a previous study by the authors. The simplified model for simulation and correction of probe head errors and its verification was proposed. This paper describes the challenges that must be faced before the final implementation of a fully functional virtual model of five-axis coordinate measuring systems.